Princess Helena of Nassau (German: Prinzessin Helene Wilhelmine Henriette Pauline Marianne von Nassau-Weilburg; 18 August 1831 – 27 October 1888) was a daughter of William, Duke of Nassau, and consort of George Victor, Prince of Waldeck and Pyrmont.

She was the ninth child of William, Duke of Nassau (1792–1839), by his second wife Princess Pauline of Württemberg (1810–1856), daughter of Prince Paul of Württemberg.

She was the half-sister of Adolphe, Grand Duke of Luxembourg (then Hereditary Prince of Nassau).

She was related to the Dutch royal family and also, distantly, to the British royal family through her father and mother, both were descendants of King George II of Great Britain.

Princess Helena married on 26 September 1853 in Wiesbaden to George Victor, Prince of Waldeck and Pyrmont, son of George II, Prince of Waldeck and Pyrmont.